After the long process of constructing the waterproof bund around the Southerly half of Burwell Fen we are nearing the point where we get to turn the key and let some water on. The plan is to increase the winter water table by a few centimetres and create some sections of permanent standing water. This is best achieved by increasing the amount of water we abstract over several years.
The water is being abstracted from Pout Hall Corner where Burwell Lode meets Reach Lode, it then runs through the intake across the bank, down the side of Reach Lode bank, through the metre and out of the end of the pipe into the stones. The stones help to reduce erosion where the water enters the fen.
The two pictures below show the abstraction point nearing completion.
The map shows the maximum water coverage within the waterproof bund. This will be the case in a few years with a spot of luck. I do want to stress that it shows the highest level of coverage during the seasonal water level change, where the water table rises in the winter and falls in the summer. With the exception of the borrow pit at the East end of the map the water will only be several inches deep before it falls away in the summer. It is worth noting that the whole area is below sea level so the high water level is at -1.4m.
This is great news! I know how large Burwell is, won't Wicken fen effectively double in size once this is complete? Keep up the good work John, I can't wait to visit Wicken and see how things are progressing :)
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